As a process cartridge mountable in an electrophotographic printer, there has been known a process cartridge including a photosensitive member for carrying a developer image, and a developing roller for supplying developer to the photosensitive member.
For example, there is proposed a process cartridge including: a process casing having a photosensitive drum; and a developing unit having a developing roller and detachably attachable to the process casing.
In this process cartridge, the developing unit is urged toward the photosensitive drum so that the developing roller is constantly in pressure contact with the photosensitive drum.
When this process cartridge is not mounted on a main body of a printer, a cover is put thereon so as to cover the photosensitive drum. The cover is provided with a pair of separation members designed to separate the developing roller from the photosensitive drum.